Abstract

In this study, bacterial strain KM221 was isolated from coral tissue in Menjangan Kecil Island, Karimunjawa, Indonesia. This
strain is facultative anaerobic with MCPA (2-methyl-4-chlorophenoxy acetic acid) serving as the only known energy sources.
Microscopy of isolate revealed that strain KM221 is gram-positive, catalase-positive, rod, spore-forming bacterium, motile,
opaque, hair-like outgrowth and unpigmented colonies. The bacterium could not be identified on the basis of its carbon-sourceutilization
pattern, but a partial sequencing of the 16S rDNA analysis suggest that this strain is closely related to Bacillus
iodinum.The ability to degrade MCPA herbicide was examined qualitatively in EMBA indicator medium. This bacterium grew
exponentially with MCPA as the sole source of energy and carbon. The maximum growth rate (μ max) and the saturated
concentration on MCPA (Cs) were determined to be 0.8024 h-1 and 5.10 mg/l MCPA, respectively.